| Message |
from an engineering standpoint. The exhaust gasses exiting the turbo's are anything but laminar already, and you are probabaly way into the turbulent regeime where increasing turbulence probably won't do much for lowering your friction factor, as the curves on the Moody diagram level out after about a Reynold's number of 10^5 no matter what e/D ratio you have. But, as you decrease the diameter you increase your "q" for the same flow rate. And pressure drop = k*q with k being a function of radius of bend over pipe diameter for bends. You get a similar "k" for area changes(such as at the flanges, etc, or when the exhaust "dumps" into the canister section of an OE exhaust) So, reduced diameter would cause more backpressure on the turbo's from the bends and area changes, even if the straight line friction drops marginally, causing the turbo's to pump less air overall. Like I said, I'm no turbo expert, but at first glamce bigger would seem to be better for your flow. You could do some fairly straighforward calculations to show which *should* be better analytically. Mike
------------------------------------------------------
 
|  |
